ScreenCapture.ahk

#include thirdParty/GDIp.ahk

/* CaptureScreen(aRect, bCursor, sFileTo, nQuality)
1) If the optional parameter bCursor is True, captures the cursor too.
2) If the optional parameter sFileTo is 0, set the image to Clipboard.
   If it is omitted or "", saves to screen.bmp in the script folder,
   otherwise to sFileTo which can be BMP/JPG/PNG/GIF/TIF.
3) The optional parameter nQuality is applicable only when sFileTo is JPG. Set it to the desired quality level of the resulting JPG, an integer between 0 - 100.
4) If aRect is 0/1/2/3, captures the entire desktop/active window/active client area/active monitor.
5) aRect can be comma delimited sequence of coordinates, e.g., "Left, Top, Right, Bottom" or "Left, Top, Right, Bottom, Width_Zoomed, Height_Zoomed".
   In this case, only that portion of the rectangle will be captured. Additionally, in the latter case, zoomed to the new width/height, Width_Zoomed/Height_Zoomed.

Example:
CaptureScreen(0)
CaptureScreen(1)
CaptureScreen(2)
CaptureScreen(3)
CaptureScreen("100, 100, 200, 200")
CaptureScreen("100, 100, 200, 200, 400, 400")   ; Zoomed
*/

/* Convert(sFileFr, sFileTo, nQuality)
Convert("C:\image.bmp", "C:\image.jpg")
Convert("C:\image.bmp", "C:\image.jpg", 95)
Convert(0, "C:\clip.png")   ; Save the bitmap in the clipboard to sFileTo if sFileFr is "" or 0.
*/

;CaptureScreen()
;Return

CaptureScreen(aRect = 0, bCursor = False, sFile = "", nQuality = "")
{
	If	!aRect
	{
		SysGet, nL, 76
		SysGet, nT, 77
		SysGet, nW, 78
		SysGet, nH, 79
	}
	Else If	aRect = 1
		WinGetPos, nL, nT, nW, nH, A
	Else If	aRect = 2
	{
		WinGet, hWnd, ID, A
		VarSetCapacity(rt, 16, 0)
		DllCall("GetClientRect" , "Uint", hWnd, "Uint", &rt)
		DllCall("ClientToScreen", "Uint", hWnd, "Uint", &rt)
		nL := NumGet(rt, 0, "int")
		nT := NumGet(rt, 4, "int")
		nW := NumGet(rt, 8)
		nH := NumGet(rt,12)
	}
	Else If	aRect = 3
	{
		VarSetCapacity(mi, 40, 0)
		DllCall("GetCursorPos", "int64P", pt)
		DllCall("GetMonitorInfo", "Uint", DllCall("MonitorFromPoint", "int64", pt, "Uint", 2), "Uint", NumPut(40,mi)-4)
		nL := NumGet(mi, 4, "int")
		nT := NumGet(mi, 8, "int")
		nW := NumGet(mi,12, "int") - nL
		nH := NumGet(mi,16, "int") - nT
	}
	Else
	{
		StringSplit, rt, aRect, `,, %A_Space%%A_Tab%
		nL := rt1
		nT := rt2
		nW := rt3 - rt1
		nH := rt4 - rt2
		znW := rt5
		znH := rt6
	}

	mDC := DllCall("CreateCompatibleDC", "Uint", 0)
	hBM := CreateDIBSection(mDC, nW, nH)
	oBM := DllCall("SelectObject", "Uint", mDC, "Uint", hBM)
	hDC := DllCall("GetDC", "Uint", 0)
	DllCall("BitBlt", "Uint", mDC, "int", 0, "int", 0, "int", nW, "int", nH, "Uint", hDC, "int", nL, "int", nT, "Uint", 0x40000000 | 0x00CC0020)
	DllCall("ReleaseDC", "Uint", 0, "Uint", hDC)
	If	bCursor
		CaptureCursor(mDC, nL, nT)
	DllCall("SelectObject", "Uint", mDC, "Uint", oBM)
	DllCall("DeleteDC", "Uint", mDC)
	If	znW && znH
		hBM := Zoomer(hBM, nW, nH, znW, znH)
	If	sFile = 0
		SetClipboardData(hBM)
	Else	Convert(hBM, sFile, nQuality), DllCall("DeleteObject", "Uint", hBM)
}

CaptureCursor(hDC, nL, nT)
{
	VarSetCapacity(mi, 20, 0), mi := Chr(20)
	DllCall("GetCursorInfo", "Uint", &mi)
	bShow   := NumGet(mi, 4)
	hCursor := NumGet(mi, 8)
	xCursor := NumGet(mi,12)
	yCursor := NumGet(mi,16)

	If	bShow && hCursor:=DllCall("CopyIcon", "Uint", hCursor)
	{
	VarSetCapacity(ni, 20, 0)
	DllCall("GetIconInfo", "Uint", hCursor, "Uint", &ni)
	bIcon    := NumGet(ni, 0)
	xHotspot := NumGet(ni, 4)
	yHotspot := NumGet(ni, 8)
	hBMMask  := NumGet(ni,12)
	hBMColor := NumGet(ni,16)

	DllCall("DrawIcon", "Uint", hDC, "int", xCursor - xHotspot - nL, "int", yCursor - yHotspot - nT, "Uint", hCursor)
	DllCall("DestroyIcon", "Uint", hCursor)
	If	hBMMask
	DllCall("DeleteObject", "Uint", hBMMask)
	If	hBMColor
	DllCall("DeleteObject", "Uint", hBMColor)
	}
}

Zoomer(hBM, nW, nH, znW, znH)
{
	mDC1 := DllCall("CreateCompatibleDC", "Uint", 0)
	mDC2 := DllCall("CreateCompatibleDC", "Uint", 0)
	zhBM := CreateDIBSection(mDC2, znW, znH)
	oBM1 := DllCall("SelectObject", "Uint", mDC1, "Uint",  hBM)
	oBM2 := DllCall("SelectObject", "Uint", mDC2, "Uint", zhBM)
	DllCall("SetStretchBltMode", "Uint", mDC2, "int", 4)
	DllCall("StretchBlt", "Uint", mDC2, "int", 0, "int", 0, "int", znW, "int", znH, "Uint", mDC1, "int", 0, "int", 0, "int", nW, "int", nH, "Uint", 0x00CC0020)
	DllCall("SelectObject", "Uint", mDC1, "Uint", oBM1)
	DllCall("SelectObject", "Uint", mDC2, "Uint", oBM2)
	DllCall("DeleteDC", "Uint", mDC1)
	DllCall("DeleteDC", "Uint", mDC2)
	DllCall("DeleteObject", "Uint", hBM)
	Return	zhBM
}

Convert(sFileFr = "", sFileTo = "", nQuality = "")
{
	If	sFileTo  =
		sFileTo := A_ScriptDir . "\screen.bmp"
	SplitPath, sFileTo, , sDirTo, sExtTo, sNameTo

	If Not	hGdiPlus := DllCall("LoadLibrary", "str", "gdiplus.dll")
		Return	sFileFr+0 ? SaveHBITMAPToFile(sFileFr, sDirTo . "\" . sNameTo . ".bmp") : ""
	VarSetCapacity(si, 16, 0), si := Chr(1)
	DllCall("gdiplus\GdiplusStartup", "UintP", pToken, "Uint", &si, "Uint", 0)

	If	!sFileFr
	{
		DllCall("OpenClipboard", "Uint", 0)
		If	 DllCall("IsClipboardFormatAvailable", "Uint", 2) && (hBM:=DllCall("GetClipboardData", "Uint", 2))
		DllCall("gdiplus\GdipCreateBitmapFromHBITMAP", "Uint", hBM, "Uint", 0, "UintP", pImage)
		DllCall("CloseClipboard")
	}
	Else If	sFileFr Is Integer
		DllCall("gdiplus\GdipCreateBitmapFromHBITMAP", "Uint", sFileFr, "Uint", 0, "UintP", pImage)
	Else	DllCall("gdiplus\GdipLoadImageFromFile", "Uint", Unicode4Ansi(wFileFr,sFileFr), "UintP", pImage)

	DllCall("gdiplus\GdipGetImageEncodersSize", "UintP", nCount, "UintP", nSize)
	VarSetCapacity(ci,nSize,0)
	DllCall("gdiplus\GdipGetImageEncoders", "Uint", nCount, "Uint", nSize, "Uint", &ci)
	Loop, %	nCount
		If	InStr(Ansi4Unicode(NumGet(ci,76*(A_Index-1)+44)), "." . sExtTo)
		{
			pCodec := &ci+76*(A_Index-1)
			Break
		}
	If	InStr(".JPG.JPEG.JPE.JFIF", "." . sExtTo) && nQuality<>"" && pImage && pCodec
	{
	DllCall("gdiplus\GdipGetEncoderParameterListSize", "Uint", pImage, "Uint", pCodec, "UintP", nSize)
	VarSetCapacity(pi,nSize,0)
	DllCall("gdiplus\GdipGetEncoderParameterList", "Uint", pImage, "Uint", pCodec, "Uint", nSize, "Uint", &pi)
	Loop, %	NumGet(pi)
		If	NumGet(pi,28*(A_Index-1)+20)=1 && NumGet(pi,28*(A_Index-1)+24)=6
		{
			pParam := &pi+28*(A_Index-1)
			NumPut(nQuality,NumGet(NumPut(4,NumPut(1,pParam+0)+20)))
			Break
		}
	}

	If	pImage
		pCodec	? DllCall("gdiplus\GdipSaveImageToFile", "Uint", pImage, "Uint", Unicode4Ansi(wFileTo,sFileTo), "Uint", pCodec, "Uint", pParam) : DllCall("gdiplus\GdipCreateHBITMAPFromBitmap", "Uint", pImage, "UintP", hBitmap, "Uint", 0) . SetClipboardData(hBitmap), DllCall("gdiplus\GdipDisposeImage", "Uint", pImage)

	DllCall("gdiplus\GdiplusShutdown" , "Uint", pToken)
	DllCall("FreeLibrary", "Uint", hGdiPlus)
}

;CreateDIBSection(hDC, nW, nH, bpp = 32, ByRef pBits = "")
;{
	;NumPut(VarSetCapacity(bi, 40, 0), bi)
	;NumPut(nW, bi, 4)
	;NumPut(nH, bi, 8)
	;NumPut(bpp, NumPut(1, bi, 12, "UShort"), 0, "Ushort")
	;NumPut(0,  bi,16)
	;Return	DllCall("gdi32\CreateDIBSection", "Uint", hDC, "Uint", &bi, "Uint", 0, "UintP", pBits, "Uint", 0, "Uint", 0)
;}

SaveHBITMAPToFile(hBitmap, sFile)
{
	DllCall("GetObject", "Uint", hBitmap, "int", VarSetCapacity(oi,84,0), "Uint", &oi)
	hFile:=	DllCall("CreateFile", "Uint", &sFile, "Uint", 0x40000000, "Uint", 0, "Uint", 0, "Uint", 2, "Uint", 0, "Uint", 0)
	DllCall("WriteFile", "Uint", hFile, "int64P", 0x4D42|14+40+NumGet(oi,44)<<16, "Uint", 6, "UintP", 0, "Uint", 0)
	DllCall("WriteFile", "Uint", hFile, "int64P", 54<<32, "Uint", 8, "UintP", 0, "Uint", 0)
	DllCall("WriteFile", "Uint", hFile, "Uint", &oi+24, "Uint", 40, "UintP", 0, "Uint", 0)
	DllCall("WriteFile", "Uint", hFile, "Uint", NumGet(oi,20), "Uint", NumGet(oi,44), "UintP", 0, "Uint", 0)
	DllCall("CloseHandle", "Uint", hFile)
}

SetClipboardData(hBitmap)
{
	DllCall("GetObject", "Uint", hBitmap, "int", VarSetCapacity(oi,84,0), "Uint", &oi)
	hDIB :=	DllCall("GlobalAlloc", "Uint", 2, "Uint", 40+NumGet(oi,44))
	pDIB :=	DllCall("GlobalLock", "Uint", hDIB)
	DllCall("RtlMoveMemory", "Uint", pDIB, "Uint", &oi+24, "Uint", 40)
	DllCall("RtlMoveMemory", "Uint", pDIB+40, "Uint", NumGet(oi,20), "Uint", NumGet(oi,44))
	DllCall("GlobalUnlock", "Uint", hDIB)
	DllCall("DeleteObject", "Uint", hBitmap)
	DllCall("OpenClipboard", "Uint", 0)
	DllCall("EmptyClipboard")
	DllCall("SetClipboardData", "Uint", 8, "Uint", hDIB)
	DllCall("CloseClipboard")
}

Unicode4Ansi(ByRef wString, sString)
{
	nSize := DllCall("MultiByteToWideChar", "Uint", 0, "Uint", 0, "Uint", &sString, "int", -1, "Uint", 0, "int", 0)
	VarSetCapacity(wString, nSize * 2)
	DllCall("MultiByteToWideChar", "Uint", 0, "Uint", 0, "Uint", &sString, "int", -1, "Uint", &wString, "int", nSize)
	Return	&wString
}

Ansi4Unicode(pString)
{
	nSize := DllCall("WideCharToMultiByte", "Uint", 0, "Uint", 0, "Uint", pString, "int", -1, "Uint", 0, "int",  0, "Uint", 0, "Uint", 0)
	VarSetCapacity(sString, nSize)
	DllCall("WideCharToMultiByte", "Uint", 0, "Uint", 0, "Uint", pString, "int", -1, "str", sString, "int", nSize, "Uint", 0, "Uint", 0)
	Return	sString
}